Doc. 37. Hygienic design and application of sensors - japanese version

EHEDG 2007
Seiten / pages: 33



According to their working principles, all sensors rely on an interaction with the material to be processed. Therefore, the use of sensors is commonly associated with hygiene risks. In many cases, the basic measuring aspect of a sensor and the optimum hygienic design may conflict. This guideline is intended to advise both, sensor designers and manufacturers as well as those in charge of production machinery, plants and processes about the appropriate choice of sensors and the most suitable way for application in dry and wet processes. Sensors are crucial in the monitoring of the critical process steps as well as the CCP´s as established by the HACCP study of the process. Therefore validation and calibration of sensors in time sequences are essential. This guideline applies to all sensors coming into contact with liquids and other products to be processed hygienically. However, it focuses upon sensors for the most common process parameters, particularly temperature, pressure, conductivity, flow, level, pH value, dissolved oxygen concentration and optical systems like turbidity or colour measurements.